There are only a relatively few pediculicides which are commercially available today. The most popular pediculicidal toxicants are Lindane (gamma benzene hexachloride), Malathion [(S-1,2-dicarbethoxyethyl)-O,O-dimethyl phosphorodithioate], synergized pyrethrins and Cuprex (a combination of tetrahydronaphthalene, copper oleate and acetone, the acetone not asserted to be active). Because of increased concern about the overall safety of some of the known ectoparasitic toxicants, the search for new, safe and effective pediculicides has intensified recently.
Many species of insects encase their ova in protective sheaths which are impregnable to most toxicants. The "gestation" period of the egg is often relatively long in comparison to the life cycle of the adult forms. Thus, an agent effective only against adults must persist for the lifetime of the developing ovum or must be reapplied as successive hatching occurs.
It has now been found that linear siloxane polymers exhibit pediculicidal and/or ovicidal activity. These compounds are known materials. For example, simethicone is widely used as an antiflatulent.
It is the object of this invention to provide new safe and effective toxicants for lice and their ova. This and other objects of the invention will become apparent to those skilled in the art from the following detailed description.